How to implement downloading files from the server to the client?

Question

JavaScript

The downloads are located outside the project folder. I can't figure out how to get the file in this case.

Answer 1

If they are within the server, you can go up to the directory above ( ../ )
There must be read permissions from this directory
ps which is fundamentally wrong.
If on another server, then as "absolute links" have already written

Answer 2

Probably it's not about the paths, but about downloading?
Here it may be:

function downloadFile($file, $fileName, $ctype) {
        if (file_exists($file)) {
            if(ob_get_level()!==0) ob_clean();
            header('Content-Description: File Transfer');
            header('Content-Type: '.$ctype.'');
            header('Content-Length: ' . filesize($file));
            header('Content-Disposition: attachment; filename=' . $fileName);
            readfile($file);
            unlink($file);
            exit;
        }